3. Martin

3. Martin

Martin: South/South East London (Property Developer)

Martin is a builder and property developer and owns several properties across South/South East London. Like all developers he always seeks ways to get the best return upon his investment.

We were invited to tender on two new proposed two bedroom basements flats, to be built below an existing purpose built mansion house. The footprint of which was an area of approximately 290 m2 . The design and planning application process was already in hand, along with the structural design by Martin’s own engineer.

What was immediately bought to our attention was the very poor ground conditions, together with the high water table. The makeup of the ground was what we refer to as River Terrace Gravel, a gravelly sand, with little firm soil to build upon. Worse than that, there was standing water from about two meters below the ground.

Our construction formation level for the basement was due to be more than 3.5 meters below the ground, which in turn meant that we needed to install a basement into more than 1.5 meters of sitting ground water! After carrying out some further research we were able to collaborate with a specialist ground dewatering company and redesign the construction, allowing for a method of dewatering within the vicinity that wouldn’t prove to be a danger to the other neighbouring properties while the water table was lowered and some changes made to the ground conditions

A whole new method was devised and built into the Construction plan.

In this instance Martin had decided to have the two flats on the ground floor vacated throughout the duration of the works. This had to be taken into account as an additional cost factor to him. Whilst it is of the upmost importance that the occupants’ safety and welfare should be a priority when carrying out construction works, we remain confident that the works could have been completed with the ground floor properties still being occupied.

However even with the additional costs, combined with the dewatering and design works, our client was able to convert an area for which there was previously no use or value into one that can be valued at over £4,300 per m2!

Our client been a builder, took care of the build fit out himself there we do not have the actual overall development cost but from our subsequent discussions we are quite confident that the total conversion cost would be below £3,300 per m2.